In high-speed textile machines, such as circular knitting machines, the needle latch is subjected to very great stresses. When the latch pivots between its closed position and its open or rear position with a frequency of up to 60 Hz and higher, as is usually the case at present, large forces of acceleration and deceleration arise at the needle latch. These forces not only stress needle latch by bending, but when the spoon strikes the hook or when the latch spine strikes the seating surfaces provided on the needle shank, considerably energies must be absorbed by resilient, elastic deformation and nullified by friction. As a consequence of these severe stresses, not only can the spoon and the hook be damaged, but the latch can also break, or damage can occur to the latch pivot and the needle shank.
It is known (U.S. Pat. No. 4,294,086, to which German Patent 27 14 607 corresponds) to dampen the impact of the needle latch in the rear position by means of a special arrangement of the longitudinal slot of the needle and thereby to avoid damage to the needle latch and the needle itself that might occur in the rear position of the latch. As a result of the cooperation between the needle shank side portions flanking the longitudinal slot of the needle and the wedge-shaped converging flanks of the seating surface on the latch spine, the side portions of the needle shank are spread apart elastically upon the impact of the needle latch, and at the same time friction is produced at the seating surfaces upon engagement with one another on the latch spine and the side portions of the needle shank. The overall result is that the needle latch is braked and damped. The elastic spreading of the needle shank side portions is limited, however, by the fact that the elasticity of the side portions of the shank decreases with increasing needle shank thickness.
Needles with pivoted blades, also known as Stelos point needles, are used for mending stockings or other knitted goods, see U.S. Pat. No. 2,596,311, Vitoux. In these needles, the forces of the pivoting blade acting on the hook are reduced by through- or penetrating holes or recesses, reduced thicknesses, or lightweight materials. In the Stelos point needles, the blade has a formed-on extension which is several times longer than the distance between the pivot and the hook, to project substantially beyond a nose which cooperates with the needle hook. Because this long extension end naturally places great stress on the needle latch, and in particular on that part of the latch which cooperates with the needle hook, it is formed with through-holes, or has an overall reduced wall thickness in comparison to the portion between the pivot and the hook, in order to reduce its weight. The blade of these Stelos point needles, which cannot be compared with standard knitting machine latch needles, is relatively massive and is not formed with a latch spoon.